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Research of Anti-spam System Basing on Immunity Systemand Mobile Agent
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作者 HUI Bei WU Yue +1 位作者 JI Lin CHEN Jia 《现代电子技术》 2007年第3期62-64,共3页
The human immune system has the function of selfdiscern.It can identify the non-self antigen and clear it through the immune response automatically.So,human body has the power of resisting disease.The anti-spam system... The human immune system has the function of selfdiscern.It can identify the non-self antigen and clear it through the immune response automatically.So,human body has the power of resisting disease.The anti-spam system basing on immune system is proposed by using immune system′s theory,and it is introduced in the mail service of enterprise VPN.Regard VPN as the human body,the mobile agent is simulated the antibody because of its movable and intelligent,and the spam is simulated the antigen.It can clear the spam by using immune mechanism.This method is a new thinking of anti-spam mail.The advantage is overcoming the weakness on independence of traditional antispam system. 展开更多
关键词 免疫系统 移动AGENT 免疫响应 虚拟网络 垃圾邮件
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Context-Aware Spam Detection Using BERT Embeddings with Multi-Window CNNs
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作者 Sajid Ali Qazi Mazhar Ul Haq +3 位作者 Ala Saleh Alluhaidan Muhammad Shahid Anwar Sadique Ahmad Leila Jamel 《Computer Modeling in Engineering & Sciences》 2026年第1期1296-1310,共15页
Spam emails remain one of the most persistent threats to digital communication,necessitating effective detection solutions that safeguard both individuals and organisations.We propose a spam email classification frame... Spam emails remain one of the most persistent threats to digital communication,necessitating effective detection solutions that safeguard both individuals and organisations.We propose a spam email classification frame-work that uses Bidirectional Encoder Representations from Transformers(BERT)for contextual feature extraction and a multiple-window Convolutional Neural Network(CNN)for classification.To identify semantic nuances in email content,BERT embeddings are used,and CNN filters extract discriminative n-gram patterns at various levels of detail,enabling accurate spam identification.The proposed model outperformed Word2Vec-based baselines on a sample of 5728 labelled emails,achieving an accuracy of 98.69%,AUC of 0.9981,F1 Score of 0.9724,and MCC of 0.9639.With a medium kernel size of(6,9)and compact multi-window CNN architectures,it improves performance.Cross-validation illustrates stability and generalization across folds.By balancing high recall with minimal false positives,our method provides a reliable and scalable solution for current spam detection in advanced deep learning.By combining contextual embedding and a neural architecture,this study develops a security analysis method. 展开更多
关键词 E-mail spam detection BERT embedding text classification CYBERSECURITY CNN
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An Online Malicious Spam Email Detection System Using Resource Allocating Network with Locality Sensitive Hashing 被引量:1
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作者 Siti-Hajar-Aminah Ali Seiichi Ozawa +2 位作者 Junji Nakazato Tao Ban Jumpei Shimamura 《Journal of Intelligent Learning Systems and Applications》 2015年第2期42-57,共16页
In this paper, we propose a new online system that can quickly detect malicious spam emails and adapt to the changes in the email contents and the Uniform Resource Locator (URL) links leading to malicious websites by ... In this paper, we propose a new online system that can quickly detect malicious spam emails and adapt to the changes in the email contents and the Uniform Resource Locator (URL) links leading to malicious websites by updating the system daily. We introduce an autonomous function for a server to generate training examples, in which double-bounce emails are automatically collected and their class labels are given by a crawler-type software to analyze the website maliciousness called SPIKE. In general, since spammers use botnets to spread numerous malicious emails within a short time, such distributed spam emails often have the same or similar contents. Therefore, it is not necessary for all spam emails to be learned. To adapt to new malicious campaigns quickly, only new types of spam emails should be selected for learning and this can be realized by introducing an active learning scheme into a classifier model. For this purpose, we adopt Resource Allocating Network with Locality Sensitive Hashing (RAN-LSH) as a classifier model with a data selection function. In RAN-LSH, the same or similar spam emails that have already been learned are quickly searched for a hash table in Locally Sensitive Hashing (LSH), in which the matched similar emails located in “well-learned” are discarded without being used as training data. To analyze email contents, we adopt the Bag of Words (BoW) approach and generate feature vectors whose attributes are transformed based on the normalized term frequency-inverse document frequency (TF-IDF). We use a data set of double-bounce spam emails collected at National Institute of Information and Communications Technology (NICT) in Japan from March 1st, 2013 until May 10th, 2013 to evaluate the performance of the proposed system. The results confirm that the proposed spam email detection system has capability of detecting with high detection rate. 展开更多
关键词 MALICIOUS spam EMAIL Detection system INCREMENTAL Learning Resource Allocating Network LOCALITY Sensitive HASHING
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Efficient Spam Filtering System Based on Smart Cooperative Subjective and Objective Methods
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作者 Samir A. Elsagheer Mohamed 《International Journal of Communications, Network and System Sciences》 2013年第2期88-99,共12页
Most of the spam filtering techniques are based on objective methods such as the content filtering and DNS/reverse DNS checks. Recently, some cooperative subjective spam filtering techniques are proposed. Objective me... Most of the spam filtering techniques are based on objective methods such as the content filtering and DNS/reverse DNS checks. Recently, some cooperative subjective spam filtering techniques are proposed. Objective methods suffer from the false positive and false negative classification. Objective methods based on the content filtering are time consuming and resource demanding. They are inaccurate and require continuous update to cope with newly invented spammer’s tricks. On the other side, the existing subjective proposals have some drawbacks like the attacks from malicious users that make them unreliable and the privacy. In this paper, we propose an efficient spam filtering system that is based on a smart cooperative subjective technique for content filtering in addition to the fastest and the most reliable non-content-based objective methods. The system combines several applications. The first is a web-based system that we have developed based on the proposed technique. A server application having extra features suitable for the enterprises and closed work groups is a second part of the system. Another part is a set of standard web services that allow any existing email server or email client to interact with the system. It allows the email servers to query the system for email filtering. They can also allow the users via the mail user agents to participate in the subjective spam filtering problem. 展开更多
关键词 ANTI-spam system Objective spam FILTERING Cooperative SUBJECTIVE spam FILTERING WEB Application WEB Services
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A Heuristic Reputation Based System to Detect Spam Activities in a Social Networking Platform, HRSSSNP
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作者 Manoj Rameshchandra Thakur Sugata Sanyal 《Social Networking》 2013年第1期42-45,共4页
The introduction of the social networking platform has drastically affected the way individuals interact. Even though most of the effects have been positive, there exist some serious threats associated with the intera... The introduction of the social networking platform has drastically affected the way individuals interact. Even though most of the effects have been positive, there exist some serious threats associated with the interactions on a social networking website. A considerable proportion of the crimes that occur are initiated through a social networking platform [1]. Almost 33% of the crimes on the internet are initiated through a social networking website [1]. Moreover activities like spam messages create unnecessary traffic and might affect the user base of a social networking platform. As a result preventing interactions with malicious intent and spam activities becomes crucial. This work attempts to detect the same in a social networking platform by considering a social network as a weighted graph wherein each node, which represents an individual in the social network, stores activities of other nodes with respect to itself in an optimized format which is referred to as localized data set. The weights associated with the edges in the graph represent the trust relationship between profiles. The weights of the edges along with the localized data set are used to infer whether nodes in the social network are compromised and are performing spam or malicious activities. 展开更多
关键词 spam Social GRAPH Collaborative Filtering Weighted GRAPH LOCALIZED Data-Set Trust Level
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ExplainableDetector:Exploring transformer-based language modeling approach for SMS spam detection with explainability analysis
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作者 Mohammad Amaz Uddin Muhammad Nazrul Islam +2 位作者 Leandros Maglaras Helge Janicke Iqbal H.Sarker 《Digital Communications and Networks》 2025年第5期1504-1518,共15页
Short Message Service(SMS)is a widely used and cost-effective communication medium that has unfortunately become a frequent target for unsolicited messages-commonly known as SMS spam.With the rapid adoption of smartph... Short Message Service(SMS)is a widely used and cost-effective communication medium that has unfortunately become a frequent target for unsolicited messages-commonly known as SMS spam.With the rapid adoption of smartphones and increased Internet connectivity,SMS spam has emerged as a prevalent threat.Spammers have recognized the critical role SMS plays in today’s modern communication,making it a prime target for abuse.As cybersecurity threats continue to evolve,the volume of SMS spam has increased substantially in recent years.Moreover,the unstructured format of SMS data creates significant challenges for SMS spam detection,making it more difficult to successfully combat spam attacks.In this paper,we present an optimized and fine-tuned transformer-based Language Model to address the problem of SMS spam detection.We use a benchmark SMS spam dataset to analyze this spam detection model.Additionally,we utilize pre-processing techniques to obtain clean and noise-free data and address class imbalance problem by leveraging text augmentation techniques.The overall experiment showed that our optimized fine-tuned BERT(Bidirectional Encoder Representations from Transformers)variant model RoBERTa obtained high accuracy with 99.84%.To further enhance model transparency,we incorporate Explainable Artificial Intelligence(XAI)techniques that compute positive and negative coefficient scores,offering insight into the model’s decision-making process.Additionally,we evaluate the performance of traditional machine learning models as a baseline for comparison.This comprehensive analysis demonstrates the significant impact language models can have on addressing complex text-based challenges within the cybersecurity landscape. 展开更多
关键词 CYBERSECURITY Machine learning Large language model spam detection Text analytics Explainable AI Fine-tuning TRANSFORMER
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DaC-GANSAEBF:Divide and Conquer-Generative Adversarial Network-Squeeze and Excitation-Based Framework for Spam Email Identification
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作者 Tawfeeq Shawly Ahmed A.Alsheikhy +4 位作者 Yahia Said Shaaban M.Shaaban Husam Lahza Aws I.Abu Eid Abdulrahman Alzahrani 《Computer Modeling in Engineering & Sciences》 2025年第3期3181-3212,共32页
Email communication plays a crucial role in both personal and professional contexts;however,it is frequently compromised by the ongoing challenge of spam,which detracts from productivity and introduces considerable se... Email communication plays a crucial role in both personal and professional contexts;however,it is frequently compromised by the ongoing challenge of spam,which detracts from productivity and introduces considerable security risks.Current spam detection techniques often struggle to keep pace with the evolving tactics employed by spammers,resulting in user dissatisfaction and potential data breaches.To address this issue,we introduce the Divide and Conquer-Generative Adversarial Network Squeeze and Excitation-Based Framework(DaC-GANSAEBF),an innovative deep-learning model designed to identify spam emails.This framework incorporates cutting-edge technologies,such as Generative Adversarial Networks(GAN),Squeeze and Excitation(SAE)modules,and a newly formulated Light Dual Attention(LDA)mechanism,which effectively utilizes both global and local attention to discern intricate patterns within textual data.This approach significantly improves efficiency and accuracy by segmenting scanned email content into smaller,independently evaluated components.The model underwent training and validation using four publicly available benchmark datasets,achieving an impressive average accuracy of 98.87%,outperforming leading methods in the field.These findings underscore the resilience and scalability of DaC-GANSAEBF,positioning it as a viable solution for contemporary spam detection systems.The framework can be easily integrated into existing technologies to enhance user security and reduce the risks associated with spam. 展开更多
关键词 Email spam fraud light dual attention squeeze and excitation divide and conquer-generative adversarial network-squeeze and excitation-based framework security
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利用SPAMS研究石家庄市冬季连续灰霾天气的污染特征及成因 被引量:66
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作者 周静博 任毅斌 +5 位作者 洪纲 路娜 李治国 李雷 李会来 靳伟 《环境科学》 EI CAS CSCD 北大核心 2015年第11期3972-3980,共9页
2014年11月18~26日石家庄市发生了连续的灰霾天气.利用位于石家庄市大气自动监测站(20 m)的单颗粒气溶胶质谱仪(SPAMS)分析了细颗粒物的化学组成,根据石家庄市大气污染物排放源谱库对主要成分进行了来源解析,并结合颗粒物质量浓度和气... 2014年11月18~26日石家庄市发生了连续的灰霾天气.利用位于石家庄市大气自动监测站(20 m)的单颗粒气溶胶质谱仪(SPAMS)分析了细颗粒物的化学组成,根据石家庄市大气污染物排放源谱库对主要成分进行了来源解析,并结合颗粒物质量浓度和气象条件研究了该地区冬季灰霾天气成因.结果表明,石家庄市大气细颗粒物来源分为7类,各源示踪离子:燃煤源为Al,工业源为OC、Fe、Pb,机动车尾气源为EC,扬尘源为Al、Ca、Si,生物质燃烧源为K和左旋葡聚糖,纯二次无机源为SO-4、NO-2和NO-3,餐饮源为HOC.灰霾期间大气中主要含有OC、HOC、EC、HEC、ECOC、富钾颗粒、矿物质和重金属等8类颗粒,其中OC和ECOC颗粒最多,分别占到总数的50%和20%以上,OC颗粒主要来自燃煤和工业工艺,ECOC颗粒主要来自燃煤和机动车尾气排放.灰霾发生时含有NH+4、SO-4、NO-2和NO-3等二次离子的颗粒物占比升高,其中含NH+4颗粒增幅最大;EC、OC与NO-3、SO-4、NH+4在灰霾天气下的混合程度均比干净天气高,其中与NH+4的混合程度加剧最为明显.冬季采暖期煤炭的大量燃烧、医化行业工艺过程及机动车尾气等污染源排放的一次气态污染物(SO2、NOx、NH3、VOCs)和一次颗粒物在静稳天气中难以扩散而迅速累积,气态污染物发生二次转化形成硝酸铵、硫酸铵,而颗粒物之间通过碰撞形成二次颗粒物并发生不同程度的混合,从而导致大气能见度下降,以上是石家庄市冬季灰霾形成的主要原因. 展开更多
关键词 灰霾 细颗粒物 污染特征 成因 spamS 石家庄市
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利用SPAMS构建石家庄市PM_(2.5)固定排放源成分谱库 被引量:24
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作者 周静博 张涛 +3 位作者 李治国 路娜 王耀涛 靳伟 《河北工业科技》 CAS 2015年第5期443-450,共8页
依托单颗粒气溶胶质谱仪(SPAMS),选取石家庄市燃煤、工业工艺、固废焚烧等固定排放源的典型企业展开了PM2.5固定排放源谱库的建立工作。通过对选取的有代表性的源排放样品进行采集和分析,获取了各排放源颗粒物的典型质谱信息和粒径分... 依托单颗粒气溶胶质谱仪(SPAMS),选取石家庄市燃煤、工业工艺、固废焚烧等固定排放源的典型企业展开了PM2.5固定排放源谱库的建立工作。通过对选取的有代表性的源排放样品进行采集和分析,获取了各排放源颗粒物的典型质谱信息和粒径分布特征。结果显示,三类污染源排放的颗粒物粒径峰值基本出现在1.0~1.5μm处;电力、水泥、制药、生活垃圾和危险废物焚烧行业排放的颗粒物粒径分布较窄,在0~3.0μm,而钢铁和医疗废物焚烧行业排放的颗粒物粒径范围较宽,在0~6.0μm左右;燃煤源的特征组分为Cr、有机低聚物、有机物和ECOC;工业工艺源的特征组分为OC,Fe,Pb,CaO,硅酸盐,有机胺;固废焚烧源的特征组分为元素碳、Pb、有机胺、Na,NaCl。该研究建立的石家庄市PM2.5固定排放源谱库,为石家庄市大气中PM2.5的在线来源解析提供了有效准确的识别依据。 展开更多
关键词 大气污染防治工程 排放源 spamS 谱库 PM2.5 石家庄市
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利用SPAMS研究华北乡村站点(曲周)夏季大气单颗粒物老化与混合状态 被引量:19
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作者 黄子龙 曾立民 +2 位作者 董华斌 李梅 朱彤 《环境科学》 EI CAS CSCD 北大核心 2016年第4期1188-1198,共11页
利用单颗粒气溶胶飞行时间质谱(SPAMS)于2013年6月30日-7月8日对华北地区乡村站点曲周大气单颗粒粒径及其化学组成进行了在线测量,共采集到同时含有正负离子谱图的颗粒230 152个,其粒径主要集中在0.2-2.0μm.结果表明,该地区的大气颗... 利用单颗粒气溶胶飞行时间质谱(SPAMS)于2013年6月30日-7月8日对华北地区乡村站点曲周大气单颗粒粒径及其化学组成进行了在线测量,共采集到同时含有正负离子谱图的颗粒230 152个,其粒径主要集中在0.2-2.0μm.结果表明,该地区的大气颗粒物主要分为8类:元素碳(EC,55.5%)、有机碳(OC,10.7%)、钠,钾等碱金属颗粒(alkalis,17.4%)、其他金属颗粒(other metals,1.7%)、富铁颗粒(Fe-rich,6.3%)、富铅颗粒物(Pb-rich,3.1%)、沙尘颗粒(dust,4.8%),other颗粒(0.8%),观测得到的8类气溶胶颗粒中绝大部分包含^46NO2^-、^62NO3^-、^80SO3^-、^96SO4^-、^97HSO4^-等二次组分离子,说明这些颗粒都经历了不同的老化过程或与二次组分进行了不同程度的混合.从气溶胶类型的谱分布看,各类型颗粒数浓度峰值基本出现在700-800 nm之间,dust、Fe颗粒主要集中在粗粒径段,EC颗粒子类研究表明随着表面不断吸附NH4^+、NO^3-、SO4^2-等二次组分,EC颗粒逐步演化成老化程度较低的NO^3-吸附型EC(ECN)和严重老化的SO4^2-吸附型EC(ECS)混合态,两者日变化呈现明显的负相关性,也可能随着二次有机物在EC表面吸附,形成OC/EC混合态. 展开更多
关键词 单颗粒 化学组成 粒径 混合状态 单颗粒气溶胶飞行时间质谱(spamS)
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利用SPAMS初探盘锦市冬季PM2.5污染特征及来源 被引量:8
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作者 邰姗姗 仇伟光 +3 位作者 张青新 祖彪 陈宗娇 王德羿 《中国环境监测》 CAS CSCD 北大核心 2017年第3期147-153,共7页
利用SPAMS 0515于2015年1月在盘锦市兴隆台空气质量自动监测点位采集PM2.5样品,并分析其污染特征和来源。研究结果表明,盘锦市冬季PM2.5的颗粒类型主要以OC颗粒、富钾颗粒、EC颗粒组成。其中,OC颗粒占比最高,为52.5%;PM2.5污染的主要贡... 利用SPAMS 0515于2015年1月在盘锦市兴隆台空气质量自动监测点位采集PM2.5样品,并分析其污染特征和来源。研究结果表明,盘锦市冬季PM2.5的颗粒类型主要以OC颗粒、富钾颗粒、EC颗粒组成。其中,OC颗粒占比最高,为52.5%;PM2.5污染的主要贡献源为燃煤、生物质燃烧、机动车尾气排放,占比分别为33.2%、25.7%、17.5%,特别是在PM2.5质量浓度较高时段,燃煤和机动车尾气排放对污染的贡献较大。 展开更多
关键词 细颗粒物 spamS 污染特征 来源 盘锦市
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一种随机嵌入抗SPAM检测的可逆数据隐藏算法 被引量:5
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作者 柳玲 陈同孝 +1 位作者 曹晨 陈玉明 《计算机应用研究》 CSCD 北大核心 2013年第7期2111-2114,共4页
针对数据隐藏算法在携带信息时容易被检测工具SPAM侦测出来这一现象,将随机嵌入和直方图修正技术应用到数据隐藏中,提出一种随机嵌入抗SPAM检测的可逆数据隐藏算法。该方法通过对采样子图与参照子图间的差值直方图进行平移空位来嵌入信... 针对数据隐藏算法在携带信息时容易被检测工具SPAM侦测出来这一现象,将随机嵌入和直方图修正技术应用到数据隐藏中,提出一种随机嵌入抗SPAM检测的可逆数据隐藏算法。该方法通过对采样子图与参照子图间的差值直方图进行平移空位来嵌入信息。在信息嵌入过程中,用随机函数产生的伪随机序列来标志待隐藏信息的位置,使嵌入的信息分布更不规律,从而更好地逃脱检测工具SPAM的侦测。实验结果表明,相比Kim算法,该算法抗SPAM检测的安全性更好,更适合进行信息传递。 展开更多
关键词 随机嵌入 spam 可逆数据隐藏 直方图修正 子图采样
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Co-Training——内容和链接的Web Spam检测方法 被引量:4
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作者 魏小娟 李翠平 陈红 《计算机科学与探索》 CSCD 2010年第10期899-908,共10页
Web spam是指通过内容作弊和网页间链接作弊来欺骗搜索引擎,从而提升自身搜索排名的作弊网页,它干扰了搜索结果的准确性和相关性。提出基于Co-Training模型的Web spam检测方法,使用了网页的两组相互独立的特征——基于内容的统计特征和... Web spam是指通过内容作弊和网页间链接作弊来欺骗搜索引擎,从而提升自身搜索排名的作弊网页,它干扰了搜索结果的准确性和相关性。提出基于Co-Training模型的Web spam检测方法,使用了网页的两组相互独立的特征——基于内容的统计特征和基于网络图的链接特征,分别建立两个独立的基本分类器;使用Co-Training半监督式学习算法,借助大量未标记数据来改善分类器质量。在WEB SPAM-UK2007数据集上的实验证明:算法改善了SVM分类器的效果。 展开更多
关键词 WEB spam检测方法 内容作弊 链接作弊 Co—Training算法
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小鼠精子透明质酸酶SPAM1在受精过程中的功能研究 被引量:2
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作者 周崇 黄莉 +2 位作者 石德顺 蒋建荣 马场忠 《畜牧兽医学报》 CAS CSCD 北大核心 2017年第4期652-659,共8页
旨在研究小鼠精子透明质酸酶SPAM1(Sperm adhesion molecule 1)对受精过程中精子/卵丘互作的影响,并初步探讨其可能的作用机制。本研究抽提小鼠尾尖基因组,利用PCR法检测小鼠Spam基因型;筛选的野生型(WT)和Spam1敲除(KO)小鼠,提取附睾... 旨在研究小鼠精子透明质酸酶SPAM1(Sperm adhesion molecule 1)对受精过程中精子/卵丘互作的影响,并初步探讨其可能的作用机制。本研究抽提小鼠尾尖基因组,利用PCR法检测小鼠Spam基因型;筛选的野生型(WT)和Spam1敲除(KO)小鼠,提取附睾尾部精子蛋白进行Western blot和酶活性检测;经TYH培养液2h获能后,分别对精子的运动性、穿透和分散卵丘细胞能力及体外受精(IVF)进行统计分析。结果表明,KO小鼠精子中未检测到SPAM1蛋白,透明质酸酶活性也极显著低于WT小鼠(P<0.01);而获能后精子运动性,在KO和WT小鼠之间差异不显著(P>0.05);与WT相比,KO小鼠精子缺失Spam1后,极显著地影响卵丘细胞层基质中精子顶体反应的发生比率(P<0.01),导致精子穿透卵丘细胞层的能力极显著降低(P<0.01),仅有少数精子能够到达卵子透明带表面,大量精子极易黏附于卵丘细胞层表面或外部边缘(P<0.01);此外,KO小鼠精子IVF 2h的卵丘细胞分散和受精率均呈现显著延迟(P<0.05)。综上表明,小鼠精子透明质酸酶SPAM1与顶体反应相关联并影响精子/卵丘互作。揭示SPAM1在穿卵过程中除了具有降解透明质酸的作用外,还存在其他的非酶活性功能。 展开更多
关键词 spam1 精子/卵丘互作 顶体反应 精子 小鼠
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SPAMS打击率影响因素与仪器状态分析 被引量:2
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作者 王莉华 刘保献 +3 位作者 张大伟 张人太 安欣欣 魏强 《质谱学报》 EI CAS CSCD 北大核心 2018年第1期36-45,共10页
在北京市环境保护监测中心空气质量综合观测实验室,使用气溶胶单颗粒飞行时间质谱(SPAMS)对2013年1~12月空气颗粒物开展综合观测。实验结果表明,SPAMS打击率与测径颗粒数(siz)、大气相对湿度、颗粒物组分以及粒径有关。仪器状态正常时,... 在北京市环境保护监测中心空气质量综合观测实验室,使用气溶胶单颗粒飞行时间质谱(SPAMS)对2013年1~12月空气颗粒物开展综合观测。实验结果表明,SPAMS打击率与测径颗粒数(siz)、大气相对湿度、颗粒物组分以及粒径有关。仪器状态正常时,打击率在siz数量小、大气相对湿度低时较高,与含K^(+)、HSO_(4)^(-)、OCEC、NO_(3)^(-)的颗粒物以及粒径为0.2~0.3μm、0.3~0.4μm、0.4~0.5μm的颗粒物数量呈正相关,与0.1~0.2μm、0.5~0.6μm、0.6~0.7μm的颗粒物数量呈负相关,含NH_(4)^(+)、SiO_(3)^(-)颗粒物数量的关系与污染特征及其他环境有关。本研究通过分析打击率数值及打击率与各影响因素的关系判断仪器状态是否正常,这为提前发现常规方法难以发现的仪器故障提供了一种思路。 展开更多
关键词 PM2.5 单颗粒气溶胶飞行时间质谱(spamS) 打击率 仪器故障
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在线社交网络中Spam相册检测方案 被引量:1
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作者 吕少卿 张玉清 +1 位作者 刘东航 张光华 《通信学报》 EI CSCD 北大核心 2016年第9期82-91,共10页
提出一种针对Spam相册的检测方案。首先分析了Photo Spam的攻击特点以及与传统Spam的差异,在此基础上构造了12个提取及时且计算高效的特征。利用这些特征提出了有监督学习的检测模型,通过2 356个相册的训练形成Spam相册分类器,实验表明... 提出一种针对Spam相册的检测方案。首先分析了Photo Spam的攻击特点以及与传统Spam的差异,在此基础上构造了12个提取及时且计算高效的特征。利用这些特征提出了有监督学习的检测模型,通过2 356个相册的训练形成Spam相册分类器,实验表明能够正确检测到测试集中100%的Spam相册和98.2%的正常相册。最后将训练后的模型应用到包含315 115个相册的真实数据集中,检测到89 163个Spam相册,正确率达到97.2%。 展开更多
关键词 社交网络安全 PHOTO spam spam检测 人人网
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利用单颗粒气溶胶质谱仪(SPAMS)研究太原市冬季一次雾霾天气的污染特征及成因 被引量:17
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作者 冯新宇 《环境化学》 CAS CSCD 北大核心 2019年第1期177-185,共9页
2017年11月5日至6日太原市发生了一次重度污染天气,利用单颗粒气溶胶质谱仪(SPAMS)分析了细颗粒物的化学组成,根据太原市细颗粒源谱库对主要成分进行了来源解析,并结合激光雷达和气象条件研究了雾霾天气成因.结果表明,雾霾天时颗粒物主... 2017年11月5日至6日太原市发生了一次重度污染天气,利用单颗粒气溶胶质谱仪(SPAMS)分析了细颗粒物的化学组成,根据太原市细颗粒源谱库对主要成分进行了来源解析,并结合激光雷达和气象条件研究了雾霾天气成因.结果表明,雾霾天时颗粒物主要包括如下9类:有机碳颗粒(OC)、元素碳颗粒(EC)、元素-有机碳混合颗粒(ECOC)、高分子有机碳(HOC)颗粒、富钾颗粒(K-rich)、富钠颗粒(Na-rich)、左旋葡聚糖颗粒、矿物质颗粒及重金属颗粒,9类颗粒中普遍存在的二次成分表明它们都经历了一定程度的老化过程.含碳颗粒物(OC、EC)与二次颗粒物(SO2-4、NO-3、NH+4)的相关性在干净天时高于雾霾天,二次颗粒物的相关性在两种天气状况下都较高.污染物来源解析结果表明,此次重污染过程主要是由机动车尾气和燃煤引起的.激光雷达及气象数据分析表明,此次污染过程是由外来污染物传输以及风速低、湿度高、大气边界层高度降低等不利的气象条件共同作用造成的. 展开更多
关键词 单颗粒气溶胶质谱仪(spamS) 细颗粒物 污染特征 源解析 雾霾 太原
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利用SPAMS研究淮安市冬季灰霾空气污染 被引量:10
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作者 潘海燕 《环境工程》 CAS CSCD 北大核心 2015年第S1期450-452,共4页
使用单颗粒气溶胶质谱仪(SPAMS)分析了淮安市冬季大气中单颗粒PM2.5的特征。对采集到的颗粒物利用MATLAB进行处理,解析得到机动车尾气、燃煤、工业工艺源等7大颗粒物来源。初步判断,灰霾污染发生很可能是由于扩散条件不利致使燃煤及机... 使用单颗粒气溶胶质谱仪(SPAMS)分析了淮安市冬季大气中单颗粒PM2.5的特征。对采集到的颗粒物利用MATLAB进行处理,解析得到机动车尾气、燃煤、工业工艺源等7大颗粒物来源。初步判断,灰霾污染发生很可能是由于扩散条件不利致使燃煤及机动车尾气源累积,二次转化加剧而导致。 展开更多
关键词 spamS 冬季 灰霾 源解析
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Web Spam技术研究综述 被引量:3
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作者 蒋涛 张彬 《情报探索》 2007年第7期66-68,共3页
讨论了Spam的基本概念和影响,详细分析了当前各种Spamming技术,包括Term Spaming、Link Spamming和隐藏技术三种类型,这对于开发恰当的反击措施是非常有用的。
关键词 WEB spamming链接分析PageRank HITS
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Web Spam技术研究综述(英文) 被引量:1
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作者 张彬 蒋涛 徐雨明 《衡阳师范学院学报》 2008年第6期131-136,共6页
Web spamming是指故意误导搜索引擎的行为,它使得一些页面的排序值比它的应有值更高。最近几年,随着webspam的急剧增加,使得搜索引擎的搜索结果也降低了一些等级。文章首先讨论了Spam的基本概念和影响,然后详细地分析了当前的各种Spamm... Web spamming是指故意误导搜索引擎的行为,它使得一些页面的排序值比它的应有值更高。最近几年,随着webspam的急剧增加,使得搜索引擎的搜索结果也降低了一些等级。文章首先讨论了Spam的基本概念和影响,然后详细地分析了当前的各种Spamming技术,包括termspaming、link spamming和隐藏技术三种类型。我们相信本文的分析对于开发恰当的反措施是非常有用的。 展开更多
关键词 Web spamMING 链接分析 PAGE RANK HITS
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